1. Field of the Invention
The present invention relates to a clean room in which escalators are equipped between a plurality of floors of different levels, and to a method of transporting a semiconductor device in the clean room.
2. Description of the Background Art
In a clean room having floors of different levels, a vertical transport system, such as a lifter or an elevator, has heretofore been used for transporting a wafer carrier between the floors.
In connection with transportation of the wafer carrier between floors by use of the vertical transport system, the number of wafer carriers, which can be transported by a single transporting operation, is limited by the capacity of the vertical transport system.
In a case where a large number of wafer carriers are used or where the capacity of the vertical transport system is low, an operator must transport wafer carriers between floors by means of repeated use of the vertical transport system.
The vertical transport system is generally operated at a slow raising or lowering speed. Consumption of time is involved from the time the vertical transport system is called until the time the vertical transport system arrives at a position from where a call has been made.
For this reason, a long period of wait time arises in transportation of a wafer carrier between floors by use of the vertical transport system, thereby hindering efficient distribution in a clean room.
The present invention has been conceived to solve the previously-mentioned problems and a general object of the present invention is to provide a novel clean room, and is to provide a method of transporting an article such as a wafer carrier or a semiconductor device.
A more specific object of the present invention is to reduce a period of wait time required for inter-floor transportation and to achieve an efficient distribution.
According to one aspect of the present invention, in a clean room having a plurality of floors of different levels, an escalator is disposed between the plurality of floors for transporting an article between the floors.
In the clean room, since the article is transported between the floors through use of the escalator, a period of wait time to transport of the article can be shortened.
According to another aspect of the present invention, in the clean room, an article is transported between the floors through use of the escalator.
In the transporting method of the semiconductor device, an efficient distribution can be achieved.
Other objects and further features of the present invention will be apparent from the following detailed description when read in conjunction with the accompanying drawings.